CHAPTER 14 ENERGY GENERATION IN MITOCHONDRIA AND CHLOROPLASTS 2009 Garland Science Publishing Mitochondria and Oxidative Phosphorylation 14 1 The link between bond forming reactions and membrane transport processes in the mitochondria is called a chemiosmotic coupling b proton pumping c electron transfer d ATP synthesis 14 2 Describe how a standard flashlight battery can convert energy into useful work and explain how this is similar to the energy conversions in the mitochondria 14 3 Modern eucaryotes depend on mitochondria to generate most of the cell s ATP How many molecules of ATP can a single molecule of glucose generate a 30 b 2 c 20 d 36 14 4 The citric acid cycle generates NADH and FADH2 which are then used in the process of oxidative phosphorylation to make ATP If the citric acid cycle which does not use oxygen and oxidative phosphorylation are separate processes as they are then why is it that the citric acid cycle stops almost immediately when O2 is removed 14 5 Indicate whether the following statements are true or false If a statement is false explain why it is false A The number and location of mitochondria within a cell can change depending on the both the cell type and the amount of energy required B The inner mitochondrial membrane contains porins which allow pyruvate to enter for use in the citric acid cycle C The inner mitochondrial membrane is actually a series of discrete flattened membrane enclosed compartments called cristae similar to what is seen in the Golgi apparatus D The intermembrane space of the mitochondria is chemically equivalent to the cytosol with respect to pH and the small molecules present 14 6 In which of the four compartments of a mitochondrion are each of the following located A porin B C D E F the mitochondrial genome citric acid cycle enzymes proteins of the electron transport chain ATP synthase membrane transport protein for pyruvate 14 7 NADH contains a high energy bond that when cleaved donates a pair of electrons to the electron transport chain What are the immediate products of this bond cleavage a NAD OH b NAD H c NAD H d NAD H 14 8 For each of the following sentences fill in the blanks with the best word or phrase selected from the list below Not all words or phrases will be used each word or phrase should be used only once Mitochondria can use both and directly as fuel produced in the citric acid cycle donates electrons to the electron transport chain The citric acid cycle oxidizes and produces as a waste product acts as the final electron acceptor in the electron transport chain The synthesis of ATP in mitochondria is also known as acetyl groups carbon dioxide chemiosmosis fatty acids glucose NAD 14 9 NADH NADP NADPH oxidative phosphorylation oxygen pyruvate Electron transport is coupled to ATP synthesis in mitochondria in chloroplasts and in the thermophilic bacterium Methanococcus Which of the following is likely to affect the coupling of electron transport to ATP synthesis in all of these systems a a potent inhibitor of cytochrome oxidase b the removal of oxygen c the absence of light d an ADP analogue that inhibits ATP synthase 14 10 Stage 1 of oxidative phosphorylation requires the movement of electrons along the electron transport chain coupled to the pumping of protons into the intermembrane space What is the final result of these electron transfers a OH is oxidized to O2 b Pyruvate is oxidized to CO2 c O2 is reduced to H2O d H is converted to H2 14 11 Which component of the electron transport chain is required to combine the pair of electrons with molecular oxygen a cytochrome c b cytochrome b c1 complex c ubiquinone d cytochrome c oxidase 14 12 For each of the following sentences fill in the blanks with the best word or phrase selected from the list below Not all words or phrases will be used each word or phrase should be used only once NADH donates electrons to the of the three respiratory enzyme complexes in the mitochondrial electron transport chain is a small protein that acts as a mobile electron carrier in the respiratory chain transfers electrons to oxygen Electron transfer in the chain occurs in a series of reactions The first mobile electron carrier in the respiratory chain is cytochrome c cytochrome oxidase first NADH dehydrogenase oxidation oxidation reduction phosphorylation plastoquinone reduction second the cytochrome b c1 complex third ubiquinone 14 13 In oxidative phosphorylation ATP production is coupled to the events in the electron transport chain What is accomplished in the final electron transfer event in the electron transport chain a OH is oxidized to O2 b Pyruvate is oxidized to CO2 c O2 is reduced to H2O d NAD is reduced to NADH 14 14 Which of the following statements is true a Because the electrons in NADH are at a higher energy than the electrons in reduced ubiquinone the NADH dehydrogenase complex can pump more protons than can the cytochrome b c1 complex b The pH in the mitochondrial matrix is higher than the pH in the intermembrane space c The proton concentration gradient and the membrane potential across the inner mitochondrial membrane tend to work against each other in driving protons from the intermembrane space into the matrix d The difference in proton concentration across the inner mitochondrial membrane has a much larger effect than the membrane potential on the total proton motive force 14 15 Some bacteria can live both aerobically and anaerobically How does the ATP synthase in the plasma membrane of the bacterium help such bacteria to keep functioning in the absence of oxygen 14 16 Which of the following types of ion movement might be expected to require co transport of protons from the intermembrane space to the matrix inasmuch as it could not be driven by the membrane potential across the inner membrane Assume that each ion being moved is moving against its concentration gradient a import of Ca2 into the matrix from the intermembrane space b import of acetate ions into the matrix from the intermembrane space c exchange of Fe2 in the matrix for Fe3 in the intermembrane space d exchange of ATP from the matrix for ADP in the intermembrane space 14 17 The F1 portion of the mitochondrial ATP synthase comprises several different protein subunits Which subunit binds to ADP Pi and catalyzes the synthesis of ATP as a result of a conformational change a b c d 14 18 The F0 portion of the ATP synthase is a multisubunit complex that spans the inner mitochondrial membrane A What are the